| Popis: |
Evaluation on cultivated land ecological security is a significant foundation for improving the security of farmland ecosystems and the sustainable use of cultivated land.To solve the problem of asymmetric information and subjectivity in most integrated evaluations,the authors define the cultivated land ecological security,construct an evaluation index system based on the Pressure-State-Response(PSR) model,and then conduct an evaluation of the ecological security of cultivated land in China by the matter element analysis and the improved entropy method.The results show:(1) The ecological security of cultivated land in China was gradually improved from critically safe to safer from 1996 to 2010,but the correlation of "safer" was extremely weak in 2010;(2) Crucial constraints on the improvement of cultivated land ecological security include fertilizer load per unit of cultivated land,per capita cultivated land,pesticide load per unit of cultivated land,land reclamation rate,and soil erosion.For the cultivated land ecological security to be continuously improved,the economic development pattern should be transformed,land use supervision and management strengthened,and excessive consumption of land resources for economic growth reduced;green agriculture should be vigorously developed,pesticides and fertilizers applied only as needed;rural land consolidation and high-standard basic farmland construction should be strengthened,environmental protection intensified,and soil erosion effectively controlled.The evaluation index system based on the PSR model can accurately reflect the relationship between various elements of the farmland ecosystems,while the matter element analysis can reveal differentiation information of every single indicator and intermediate information of comprehensive evaluation,discovering specific problems in cultivated land ecological security.Therefore,the evaluation index system and the matter element analysis are suitable to assess the cultivated land ecological security. |
